Results 31 to 40 of about 74,507 (265)

The essential norms of composition operators [PDF]

Glasgow Mathematical Journal, 1992
Throughout the paper n denotes a fixed positive integer unless otherwise specified. Let B = Bn denote the open unit ball of ℂn and let S = Sn denote its boundary, the unit sphere. The unique rotation-invariant probability measure on 5 will be denoted by σ = σn. For n = l, we use more customary notations D = B1, T = S1 and dσ1= dθ/2π. The Hardy space on
openaire   +1 more source

The essential norm of multiplication operators on $$L_p(\mu )$$

Afrika Matematika, 2022
AbstractWe show that the formula for the essential norm of a multiplication operator on$$L_p$$Lp, for$$1<p<\infty $$1<p<∞, also holds for$$p=1$$p=1. We also provide a proof for the formula which works simultaneously for all$$p\in [1,\infty )$$p∈[1,∞).
openaire   +2 more sources

Revealing the structure of land plant photosystem II: the journey from negative‐stain EM to cryo‐EM

FEBS Letters, EarlyView.
Advances in cryo‐EM have revealed the detailed structure of Photosystem II, a key protein complex driving photosynthesis. This review traces the journey from early low‐resolution images to high‐resolution models, highlighting how these discoveries deepen our understanding of light harvesting and energy conversion in plants.
Roman Kouřil
wiley   +1 more source

Duality of the weak essential norm [PDF]

Proceedings of the American Mathematical Society, 2000
Let \(E\) and \(F\) be Banach spaces, and let \({\mathcal L}(E,F)\) be the space of all bounded linear operators from \(E\) into \(F\). Let \(W(E,F)\) denote a (closed) subspace of \({\mathcal L}(E,F)\) composed of all weakly compact operators. The weak essential norm is the quotient norm \(\|S\|_w=\text{dist}(S,W(E,F))\), \(S\in{\mathcal L}(E,F ...
openaire   +1 more source

By dawn or dusk—how circadian timing rewrites bacterial infection outcomes

FEBS Letters, EarlyView.
The circadian clock shapes immune function, yet its influence on infection outcomes is only beginning to be understood. This review highlights how circadian timing alters host responses to the bacterial pathogens Salmonella enterica, Listeria monocytogenes, and Streptococcus pneumoniae revealing that the effectiveness of immune defense depends not only
Devons Mo, Catherine S. Palmer, Jacqueline M. Kimmey   +2 more
wiley   +1 more source

Molecular bases of circadian magnesium rhythms across eukaryotes

FEBS Letters, EarlyView.
Circadian rhythms in intracellular [Mg2+] exist across eukaryotic kingdoms. Central roles for Mg2+ in metabolism suggest that Mg2+ rhythms could regulate daily cellular energy and metabolism. In this Perspective paper, we propose that ancestral prokaryotic transport proteins could be responsible for mediating Mg2+ rhythms and posit a feedback model ...
Helen K. Feord, Gerben van Ooijen
wiley   +1 more source

Interplay between circadian and other transcription factors—Implications for cycling transcriptome reprogramming

FEBS Letters, EarlyView.
This perspective highlights emerging insights into how the circadian transcription factor CLOCK:BMAL1 regulates chromatin architecture, cooperates with other transcription factors, and coordinates enhancer dynamics. We propose an updated framework for how circadian transcription factors operate within dynamic and multifactorial chromatin landscapes ...
Xinyu Y. Nie, Jerome S. Menet
wiley   +1 more source

Disordered but rhythmic—the role of intrinsic protein disorder in eukaryotic circadian timing

FEBS Letters, EarlyView.
Unstructured domains known as intrinsically disordered regions (IDRs) are present in nearly every part of the eukaryotic core circadian oscillator. IDRs enable many diverse inter‐ and intramolecular interactions that support clock function. IDR conformations are highly tunable by post‐translational modifications and environmental conditions, which ...
Emery T. Usher, Jacqueline F. Pelham
wiley   +1 more source

High-Intensity Interval Training Decreases Muscle Sympathetic Nerve Activity in Men With Essential Hypertension and in Normotensive Controls

Frontiers in Neuroscience, 2020
Exercise training is a cornerstone in reducing blood pressure (BP) and muscle sympathetic nerve activity (MSNA) in individuals with essential hypertension.
Thomas Svare Ehlers, Yrsa Sverrisdottir, Yrsa Sverrisdottir, Jens Bangsbo, Thomas Petursson Gunnarsson   +4 more
doaj   +1 more source

Weighted Composition Operators from Derivative Hardy Spaces into n-th Weighted-Type Spaces

Journal of Mathematics, 2021
The boundedness, compactness, and the essential norm of weighted composition operators from derivative Hardy spaces into n-th weighted-type spaces are investigated in this paper.
Nanhui Hu
doaj   +1 more source